Solar Panels in Ontario are exempt from property tax. This is written into the Assessment Act.
Here is the wording from the Assessment Act:
Property assessable and taxable, exemptions
3 (1) All real property in Ontario is liable to assessment and taxation, subject to the following exemptions from taxation:
Machinery for producing electric power
18. All machinery and equipment including the foundations on which they rest to the extent and in the proportion used for producing electric power but not including any buildings, structures, structural facilities or fixtures used in connection therewith.
Yay! No Property Tax on solar panels!!